SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '664712f9be8b1c7090770f9ca0e46c44dc0132632bb68f9bb59c381ad87613f7' 
  AND token = 'jZm20OBIZMaBIt9o6Ah/Di+lKoNHwHhvy7EVzgsdubg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}