SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed353fdb77cceeac6bad7db57900e471004cc60707aa03fa63c6ab5fdcb7e452' 
  AND token = 'hWVpn5xtATSmGyVaTuybBkJ4J+IVsKpgJBgOZ7U7VZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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