SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e5b45025008f1c7c096af3ab7e521d8c81285904176db735945d6c9df39728b' 
  AND token = 'bSYTeFSYXKjgwcLRulMJ6Gq3Vi6ONtsH0o8xZSbrXVk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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