SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'c0a259f37068a2f805b7e16f8f4024b658d059386995f9221e9488876a322fdd' 
  AND token = 'Ne4mzB8Eqp2iTS8aJmdC9ucN0dqaNdbw3qswoBZn8Tg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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