SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2634624bbd78257132702446c2bcd03dc004c0a21622087b20905efd2ac377f8' 
  AND token = 'RGx+o+ws8iVa2/9Ipk1iLFNvAKZyAoJeqMbD0myxxk4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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