SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '90108d9789e1ce983d023e98badd643057442e79b3781d3f3cb5e75210fe7e07' 
  AND token = 'VIjun0lP0r3l27dcda31LWoHHUqpieOYwmV4OA+n4NE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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