SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0da62630f80314af415187cf5362e212dd0b3e89644731e0212ce022f7af69b' 
  AND token = 'rZMobhOaKqrLtjAZinoCs+R/xoXbYStjmPlEK8Nm92U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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