SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd567dcd2c41618b55928e5040ccd9ad403b6f53b819d47cd8ddec6ccc4013c0' 
  AND token = 'ebnq9OIUInEyUgmtpC2KZq2bHB7LaD+HFw1X5QhV18I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}