SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9db593dfd03d47e82bcd9b4c4fda60cf5c5d5ef19b332495230d74ed5b7a6d9c' 
  AND token = '8fSzVbGYiGmMCy0bvqDi3BArbJMH5TuQ6TXtOmu2HJw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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