SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33c3c30b2090f8f305d6fe8062d1dfeca68f6c52af298d805854953b3ef1bb04' 
  AND token = 'Co7g8C4j5t6whHe6VA52ELYQO1nBOrCzyuxGuhJw/Lo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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