SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '949398dbd96aa2acca987d2b8159ae5a17d84eab328a6ced65c97f235a4d01e7' 
  AND token = 'kTjEt/ElOidMlUG1qnNg7beZqWS0RWr0Zl3BlsIHHNM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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