SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '262efc270cae15028da93258d5ef4df1ae2c9d64502989739921ab143be0677c' 
  AND token = 'xaQAJdcDBzwIFMWewKJbbj+ozzt9/yY5/p9iSwlnbXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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