SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43f460bba03fc8e2c981d82d8498ecbc141231108a4cabf6ec60ff4285e068fd' 
  AND token = 'aYHiAbJrHzvi2km3gBGzR0zSRSkGlUgel/9pPba4tYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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