SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '777207fc7600e8df69ea32582188fc58dfe13e85b4b0906394652ab4e833a3bc' 
  AND token = 'k1DCxCXeZDC0C7b57TQjiKldTRQ0OZW8uqKEzF3faGQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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