Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78739078e7a996f2635633ca45741ff66aee243d58c0982301b82b8526bd9570' 
  AND token = 'JqUxAGxprZC4bFyYkE7RtbXyL8NIrOnl+lmDboHNoDI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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