SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1104e24ec1ac492b189e8acfe22c086543494df48df89253e56125abf4381c7d' 
  AND token = 'EaKflOWRC1YIXlarOAkP0ZvWS3xNSE0qb44MTkPcjXQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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