SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2801b6cda910a109a5c85b33cf7a395474567c5093a64f9a03c2650a4bc8e924' 
  AND token = 'X8K7RgI3RPZYDlfpx+5BrrQPVTeV7P3how/7sez+3lI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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