SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ba9651f9739236cccc11758b30e32603b5fdd91d7d2dab7d4c789c7075559c2' 
  AND token = 'jVwddFHhA1XiHtGjNpmGoAvuK1/zPg9f6p6xlU0K9fQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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