SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd28482dde8359f6d70073495d2f41098027d5aa5e0667ca1b930fd37823083df' 
  AND token = 'sEUyUyFMMzDmUKmQ3bMSdBCjvF7qTNEzqT3UH6yYobk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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