SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b9d606ae3b0893d7726f98f196e0253942a3a5700dfc58fd4aae9d169a057424' 
  AND token = 'BL0QclpbNWnRCUPMhtfQ4NwYq8iFYR6vHBmg/uqpoW4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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