SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bac79ca51b14c27f02b0ec963f3f8683c96f65077321f4af107a56cdfd909989' 
  AND token = 'iZfwkXJGFglCQocKxYjANL48bGFHx05FHq8MdTJaUak=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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