SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae57cc596990722e09ed5aa68c7a695fbfa25696d8a15aad50d7792911e0d2fc' 
  AND token = 'tnN8VUlC91W2Gh/LSnzjwqwuunuMJbyl3eL1gyDkOWg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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