SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6faeb2924f2993669dd90ce1e01f446fcfb8a9cd83e0606a651a7280916ee076' 
  AND token = 'UHqTiPSVW28lETM0ZPWNpcUDLk/r2cqAt+iXAfA691o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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