SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d9330b1f84d9e5ffdcf19fd0d5f4b8ec0572d7a64971cf377b66a8c49685f68' 
  AND token = 'KNtiAiYfRleOOYedfQDfk1zqArWgbdMVsLYdPUfv5N4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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