SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3767e55b9207a1a1d43301edf1a1d98a6e981c3134cc7a3cda4ae137f78e0564' 
  AND token = 'L4zjGYBvipuWJpPRX2622+l695bJe/MQKYJ4nONlvVo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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