SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0333d9e753a7b7c22abda2e1b920297d39837d0f9072d3673b867efe44b3ea25' 
  AND token = 'EVckvpQBZmTiWW+P/9CuIie5EHMuiphpHPL7XHVrV5Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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