SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6b22264c88c8c67119eeea35ddd87fb26fb1e40ca20ca617410ec2c5be9bc65' 
  AND token = 'awZO3GMqFm+7vobh8l9x5oTCslDVsJSFzyDnx1owj0s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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