SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6648ca882080b4dad3baa7073a3bee09c00dc5574d6f9cb1014e160c3223d150' 
  AND token = 'BTYvo+0YDofMlbFinxO7u86aTk7WaHo1zB33Cna8iic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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