SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95637da70de057de8056cf9d8e86440a8310327a596b62dfb4a793b7fca442e9' 
  AND token = 'D7ZjFMmQKdZbAdRa7Oau+z2MP0Xg4+L0+s9t6d0m+j8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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