SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '94911573f48b852cad2ca46dbee70d45c3d5440a3308b83875aff115d430b193' 
  AND token = 'jb4bqe64I8xPAabZMT+pgP2rRo+Xtxi188U039IVTzY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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