SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b59f8bd82c5c4e947313f6c71bae4cacd8b5cf50f13516913413bcaff487cb7' 
  AND token = 'QKvkyeL6HJbwV8PtbBCtXwvlgo2qkVIQ69DdxBrzqY8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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