SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ca8072ecb91cf29326c2ecb51579cfc5c300d2c8b0cf38934011e32b559f340' 
  AND token = 'hb0XffDSXW8Mc9GjR/VZ3KNkV3Bh5GMXo5oULrUsrO0=' 
  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"
    }
  }
}