SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f87e69bc67c1d415d29b78d976217169ef01f105de654e9254e7c1c71664fbb7' 
  AND token = 'FB95NTMWSa9Aj0UuqiBpTTz3MmKyMe9Sl1cYZTJ9f84=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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