SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17d52958011f2f67c925d22a4d5f5c1eab7cf4eb8647dfd889a29686d3f8a9f9' 
  AND token = 'VJQyGOcYEWK8qugXo1LzPeKPuuYNDjsW8d09XTNHZ1w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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