SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5eaf3211cbf038acc881eb1be53548b1a500b82fea7e1f7c115d6e5bb9f4fe8d' 
  AND token = 'w1lW4/AA39bBhcNiccsR6WJAC3yjO/HEtkr5q78mcgw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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