SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '15f42beaabd2f5d9aec281cbf9a5f493c626b11b700c3f33365200684aa72603' 
  AND token = '2pD81iVG0ql1fPOy5+6XkWfFGHPpAAu0VkwL6sB9AXM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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