SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30c9669c1a853ba684ffc4cb2125f6f9c71a5ca943861714e91caabbf63be5ed' 
  AND token = 'mATIWqmANntoHYnpZDdLgi3Q0YW/68lhDeKlTr7jpXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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