SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'be5b0796b06fa5a7ed04da4f649a2b6ed917bbc20b3f16aa5e239a62633b3886' 
  AND token = 'K1JIhgfrQisf/ANaX7xq/jrfTYurLpGhRoqpAZpPy48=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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