SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17cd61fbca749f6d0248ca67aebc182819e77c0284f610ac10b9b7a9814e2fe6' 
  AND token = 'WbD2OVG7gXcQFXG33Mis0x4JvFxya5bOvCpQRZZMMRI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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