SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '41eb27a0f1353674f8da6c155fbc773965c218a357030c9ce077da971d1ab08e' 
  AND token = 'VBGT67IerEpQ2UbN90GrzoJdqf2G6lv1lGIffjKGhKw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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