SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c2166a9db3ef77973f2b0bb2e67937e8814b8ef5880521dff4448677452b318' 
  AND token = 'MRLrC/ZJtBG8hb8ZnOWKg40eBDFXHWAW9ZFSVR1hmBU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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