SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ad90fdb24783a03e7c60d42c5c612bd716292d6f362ad4a4822283086f9a90d4' 
  AND token = 'Woq3z6K+9ylDCifUtd4fZ7bKLcQdF7yh7wwTijxzvuI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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