SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '4f2cfe637b037cae3e7c5c99deeafa8a2ed55c56d8bbe822c0209a5c439dedc3' 
  AND token = 'Dw0AEL4O1MMFRBPW/iFTwF5hiGeA8p02tNJn/UywbnQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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