SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ee29ac3c83fd38b6b72c7a090f1c28854ee07c9edb4f87a2c9125632d146a5c' 
  AND token = 'pp2mQwOWCeKtcv9j9HO/VQCQfC+h6L/zxCsysgBKFvM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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