SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59af4f4ed021fe65293701a85e456e95c4891ebf301a6eb4dc63a3f7f6cb6e04' 
  AND token = 'K9ZSSJ6FGWswV+wP8Mjvvil3orS3E9D2/AY5PGYJ5CM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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