SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f09ea571138a0fc96d18d024a84b7c2f3ef16a3d0ed57c2ec87a3354776d12ee' 
  AND token = 'CMcBcyQkVSXtX0iE4a9FslrVnWzqVFQVgOayXNfGaUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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