SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd11cfb4b8b2f3115b095d6a0c2bfcd460658d5840bbf912433db27986af1a809' 
  AND token = 'drYqUjzoh0jhqJgS6AURLm58v4at6CIu/FjK3jKN9Sw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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