SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be98c7e85b14705aad13458e01b010f15ea41873776320b9cbf665a69253efbc' 
  AND token = 'se/fhRHQVCjOIrgjr4v7TgKd4fapYZJRc1VAB6TOWTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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