SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'c69ed91b46737c40f4b76785d078539c836200299f0abb7e42c6361f183032ee' 
  AND token = 'WxYLOccQIL4fpO/GudkPziGepCObJqiuZzb3Lu8+V+U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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