SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c067bf12204d2c7920884100f02781ef1f5c7e8951fe518df12c78396cae9a6f' 
  AND token = 'tmaeIAddd1vNzQYbJ2oyReXHU8Y9ki2U5CBSp/OmGkw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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