SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '096329f67b328a07e207f188cc47f13ba946e7ca09b547c53b6fb000998887ac' 
  AND token = '0f0w9uK4GATXVWuNFYnf2AkJcZhdjG4PjNavqomWqVY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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