SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61cb97143239b6d4d8262c4f05b048c851c79729b85a48fdc8890a142162d2f8' 
  AND token = 'IOUng2awsPexftwwSxU/PcDaCTDHYphurdzHoEFsvyQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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