SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33d9d135a19041fcd03cc039caccd9f2a21222804bef404ad5955d65137151ff' 
  AND token = 'wNv8s7cWUwsB5wuFhpxojO2RrLUV2JMu/5iVCWVpMfc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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