SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7adfb14944bd1b9fb1a1e40b99d5b7f8749c883b9f3b5b2f37333c966cd2209d' 
  AND token = 'Wbq0ILbQF+0BqWn/REqVOzNkjcw5pNGNPvu6a8kLrG4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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