SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '11fd2aca2debd218c5307dce6834cc208b004b9375efac46e004b1d75b8d8ff8' 
  AND token = 'hS7sBqmhUZQf/+Wzfaf0WdppCMho5BtglwBcVnzVrUg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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