SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ba258be3e98744100965371b97664dba25dbe7f180d02716839be500378495b' 
  AND token = 'j+wSI+pn8kQz2tfIGDcjrZwrFofVSm7t053O2y09AT8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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