SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72fc0fa62dfeab3f46c0b1e3c51a94749648f2e25b92b52ea3c278d4c4426acb' 
  AND token = 'Y3DrguOUF17sCC3ZVh5xMq2UMbQZ4dAsFk270cUrxZ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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