SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80265412278fdf55f605be605f7be12f5aee1a0015392a4fdd6aafbdd39034fd' 
  AND token = 'EYj001OY6D/2ZwcfjjP9ObAee8ifhF5jIClKUFf3QGI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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