SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '429c8674e524f905c2cc92b3d8792dc3f6e1f0eb0e5a654d831cbf61ffed8f6f' 
  AND token = 'oZtwGoyUkjVHwXeMKOLjZIUs/Io9iRaX7jvZcPocMis=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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