SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aebeddcceef21a0bf27965c8dbdea5f00354fce40a1a140b87957f717078ad6d' 
  AND token = 'vf1B1QU+AF8TjenxbFhm0vTqxQyhQtsnm2fPgY0ByPk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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