SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '383f117eab254db79bb224a74a1999924ace5703aeda8c6f1de5a3580093fca0' 
  AND token = 'XPkA1kCkHcn/Pr/c+ECw2NW0OsiFurZelk0lUTpNJjg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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