SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8099cf6e82bd45a43571842bd6781c9de11031d955153c4fa6891588afcc9e3d' 
  AND token = 'QjOhQJuWbfnaHNWRkBY+KYXgTg7/gJ+RVSr5ewMCB/0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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