SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '02e5caa499ebe638a76592045a44287ead1f47bc7e37cfe531b01ac3d2570b88' 
  AND token = 'uAbdxYe0LcIfctYhtcJBeS5aMXrsdIvgByXUWeElSeA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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