SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ff53d356923b8376289c758622e9d44358de59577e77d90f45639ffff3c156e' 
  AND token = 'xVocbrJSCbEBcvRj6yo4Je7cY/MGnH+ZJ2RK68gw4mo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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