SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9633a76d3214d1bd04ae949e270bf82212182bab995adfde9e789d732eeb65ee' 
  AND token = '2HK8OKdeEQbOvvdpuz0utgqZderhUiMC/huyaUgZnOg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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